- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Layered Ruddlesdena??Popper Perovskites with Various Thicknesses for Stable Solid-State Solar Cells
摘要： The present research comes up with optimizing the layers thickness of a Ruddlesden–Popper perovskite with the general formula of (S0.97S'0.03)2[Cs0.05(FA0.097MA0.03)0.95]n – 1Pbn(I0.97Br0.03)3n + 1 for efficient, stable solar cell applications. Such a triple-cation quasi-two-dimensional (2D) structure simultaneously contains two spacers, namely 5-ammonium valeric acid iodide (S) and tetra-n-octylammonium bromide (S'). Systematic studies showed that morphology, crystal structure, optical properties, photovoltaic performance, and internal resistances of this compound depended upon the value of the n integer. Field emission scanning electron microscopy set forth that the deposited films were composed of various morphologies depending on the n value. An increase in the n value resulted in improving the light absorption, reducing the band gap energy, and blue-shifting the photoluminescence peak. So as to fabricate solar cells, CuInS2 nanoparticles were employed as a novel hole-transporting material. The device based on the film having n = 4 value showed the highest power conversion efficiency of 10.2%. Electrochemical impedance spectroscopy demonstrated that the improved performance of this cell was mainly thanks to its low series resistance (11.68 Ω), and long electron lifetime (8.05 μs) as compared to all the fabricated cells. Moreover, this cell displayed a maximum external quantum efficiency of 82% among all the devices. The un-encapsulated solar cells showed that the output reduction directly depended on the n value so that the cell based on the n = 4 reached 82% of its initial power over 2500 h in ambient conditions.
关键词： tetra-n-octylammonium bromide,Ruddlesden–Popper structure,2D triple-cation perovskite,solar cells
更新于2025-09-23 15:21:01
-
Ultrathin Nanosheets of Oxo‐functionalized Graphene Inhibit the Ion Migration in Perovskite Solar Cells
摘要： Mixed cation/halide perovskites have led to a significant increase in the efficiency and stability of perovskite solar cells. However, mobile ionic defects inevitably exacerbate the photoinduced phase segregation and self-decomposition of the crystal structure. Herein, ultrathin 2D nanosheets of oxo-functionalized graphene/dodecylamine (oxo-G/DA) are used to solve ion migration in cesium (Cs)-formamidinium (FA)-methylammonium (MA) triple-cation-based perovskites. Based on the superconducting carbon skeleton and functional groups that provide lone pairs of electrons on it, the ultrathin 2D network structure can fit tightly on the crystals and wrap them, isolating them, and thus reducing the migration of ions within the built-in electric field of the perovskite film. As evidence of the formation of sharp crystals with different orientation within the perovskite film, moiré fringes are observed in transmission electron microscopy. Thus, a champion device with a power conversion efficiency (PCE) of 21.1% (the efficiency distribution is 18.8 ± 1.7%) and a remarkable fill factor of 81%, with reduced hysteresis and improved long-term stability, is reported. This work provides a simple method for the improvement of the structural stability of perovskite in solar cells.
关键词： Ion-migration inhibition,triple cation perovskite,oxo-functionalized graphene
更新于2025-09-12 10:27:22
-
δ‐CsPbI <sub/>3</sub> Intermediate Phase Growth Assisted Sequential Deposition Boosts Stable and High‐Efficiency Triple Cation Perovskite Solar Cells
摘要： Cs/FA/MA triple cation perovskite films have been well developed in the antisolvent dripping method, attributable to its outstanding photovoltaic and stability performances. However, a facile and effective strategy is still lacking for fabricating high-quality large-grain triple cation perovskite films via sequential deposition method a, which is one of the key technologies for high efficiency perovskite solar cells. To address this issue, a δ-CsPbI3 intermediate phase growth (CsPbI3-IPG) assisted sequential deposition method is demonstrated for the first time. The approach not only achieves incorporation of controllable cesium into (FAPbI3)1–x(MAPbBr3)x perovskite, but also enlarges the perovskite grains, manipulates the crystallization, modulates the bandgap, and improves the stability of final perovskite films. The photovoltaic performances of the devices based on these Cs/FA/MA perovskite films with various amounts of the δ-CsPbI3 intermediate phase are investigated systematically. Benefiting from moderate cesium incorporation and intermediate phase-assisted grain growth, the optimized Cs/FA/MA perovskite solar cells exhibit a significantly improved power conversion efficiency and operational stability of unencapsulated devices. This facile strategy provides new insights into the compositional engineering of triple or quadruple cation perovskite materials with enlarged grains and superior stability via a sequential deposition method.
关键词： CsPbI3 intermediate phase growth,stability,perovskite solar cells,sequential deposition,triple cation perovskite,grain growth
更新于2025-09-11 14:15:04